You don't need a truthful reason to have an excuse. Remember the whole Iraq WMD debacle?

Or, for that matter, Ukraine giving up its nuclear capabilities.

Exactly, even with conventional ammunitions they have shown a lot of restraint to avoid a nuclear response from Israel.

Israel doesn't have much in the way of a credible defense against Iranians advanced hypersonic missiles. Iran could create a mess in Israel by obliterating their de-salinization installations. If they were the blood thirsty fanatics propaganda paints them to be, that would be exactly what they would do, even knowing that in that case Israel wouldn't have much choice than making Tehran a giant glass parking lot.